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๐Ÿ”— Blast Valve

๐Ÿ”— Technology

A blast valve is used to protect a shelter, such as a fallout shelter or bunker, from the effects of sudden outside air pressure changes. A nuclear weapon creates a shock wave, which may produce sudden pressure changes of more than an atmosphere (about 1 bar) even several kilometres from the detonation point. After the shock wave passes, a sudden negative pressure follows.

If such pressure waves enter a shelter, they will likely do substantial harm to occupants and equipment. A blast valve is placed in air intake/exhaust pipes, that remains open normally, but automatically closes when strong pressure is applied in either direction. Blast dampers operate in the same fashion and are related or identical to blast valves, the former name however is generally used to describe blast mitigation devices, for more conventional explosive events.

A typical blast valve has entries of 15โ€“30ย cm diameter, and a larger centre section. Within the centre section is a disk mounted on an axle, with weak springs that keep it centred, away from both entries. Pressure displaces the disk along the axle, until it plugs one entry or the other. After the blast, the springs return the disk to the centre, re-opening the valve.

Another type of blast valve employs rounded metal tubes held in place by springs. As pressure rises it pushes the tubes against the frame of the valve closing the opening. These valves are typically unidirectional in airflow and are employed in large wall structures where large amounts of airflow is required.

One form of blast valve, popularized by the book Nuclear War Survival Skills and tested by ORNL is worn flat rubber tire treads nailed or bolted to frames strong enough to resist the maximum overpressure, with tested closing times cited as being identical to commercial grade blast valves, however the use of this form of blast valve design must also take the risk of the flammable rubber catching fire into consideration.

๐Ÿ”— Shigir Idol

๐Ÿ”— Russia ๐Ÿ”— Arts

The Shigir Sculpture, or Shigir Idol (Russian: ะจะธะณะธั€ัะบะธะน ะธะดะพะป), is the oldest known wooden sculpture in the world, made during the Mesolithic period, shortly after the end of the last Ice Age. The wood it was carved from is approximately 11,500 years old. It is displayed in the Sverdlovsk Regional Museum of Local Lore in Yekaterinburg, Russia.

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๐Ÿ”— An-225

๐Ÿ”— Aviation ๐Ÿ”— Soviet Union ๐Ÿ”— Russia ๐Ÿ”— Russia/technology and engineering in Russia ๐Ÿ”— Aviation/aircraft ๐Ÿ”— Ukraine

The Antonov An-225 Mriya (Ukrainian: ะะฝั‚ะพะฝะพะฒ ะะฝ-225 ะœั€ั–ั, lit.โ€‰'dream' or 'inspiration'; NATO reporting name: Cossack) is a strategic airlift cargo aircraft that was designed by the Antonov Design Bureau in the Ukrainian SSR within the Soviet Union during the 1980s. Originally, this unique aircraft was developed as an enlargement of the Antonov An-124 to transport Buran-class orbiters. After successfully fulfilling its Soviet military missions, it was mothballed for eight years. It was then refurbished and reintroduced into commercial operation with Antonov Airlines, carrying oversized payloads. While a second airframe with a slightly different configuration was partially built, construction was halted more than once due to a lack of funding and interest. This second aircraft was last brought up to 60โ€“70% completion in 2009.

As an over sized aircraft the Antonov An-225 Mriya holds multiple records which include; heaviest aircraft ever built, and largest wingspan of any aircraft in operational service. Other records held by the An-225 are cargo related in terms of weight and length as the Antonov An-225 has the capability to carry up to 640 tonnes (705 short tons). The An-225 attracts a high degree of public interest, so much that it has managed to attain a global following due to its size and its uniqueness. People frequently visit airports to see its scheduled arrivals and departures.

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๐Ÿ”— Project Denver

๐Ÿ”— Computing

Project Denver is the codename of a microarchitecture designed by Nvidia that implements the ARMv8-A 64/32-bit instruction sets using a combination of simple hardware decoder and software-based binary translation (dynamic recompilation) where "Denver's binary translation layer runs in software, at a lower level than the operating system, and stores commonly accessed, already optimized code sequences in a 128ย MB cache stored in main memory". Denver is a very wide in-order superscalar pipeline. Its design makes it suitable for integration with other SIPs cores (e.g. GPU, display controller, DSP, image processor, etc.) into one die constituting a system on a chip (SoC).

Project Denver is targeted at mobile computers, personal computers, servers, as well as supercomputers. Respective cores have found integration in the Tegra SoC series from Nvidia. Initially Denver cores was designed for the 28nm process node (Tegra model T132 aka "Tegra K1"). Denver 2 was an improved design that built for the smaller, more efficient 16nm node. (Tegra model T186 aka "Tegra X2").

In 2018, Nvidia released an improved design (codename: "Carmel", based on ARMv8 (64-bit; variant: ARM-v8.2 with 10-way superscalar, functional safety, dual execution, parity & ECC) got integrated into the Tegra Xavier SoC offering a total of 8 cores (or 4 dual-core pairs). The Carmel CPU core supports full Advanced SIMD (ARM NEON), VFP (Vector Floating Point), and ARMv8.2-FP16. First published testings of Carmel cores integrated in the Jetson AGX development kit by third party experts took place in September 2018 and indicated a noticeably increased performance as should expected for this real world physical manifestation compared to predecessors systems, despite all doubts the used quickness of such a test setup in general an in particular implies. The Carmel design can be found in the Tegra model T194 ("Tegra Xavier") that is designed with a 12 nm structure size.

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๐Ÿ”— Japanese Invasion Money

๐Ÿ”— Military history ๐Ÿ”— Numismatics ๐Ÿ”— Military history/World War II ๐Ÿ”— Indonesia ๐Ÿ”— Japan ๐Ÿ”— Military history/Asian military history ๐Ÿ”— Military history/Japanese military history

Japanese invasion money, officially known as Southern Development Bank Notes (Japanese: ๅคงๆฑไบœๆˆฆไบ‰่ป็ฅจ Dai Tล-A Sensล gunpyล, "Greater East Asia War military scrip"), was currency issued by the Japanese Military Authority, as a replacement for local currency after the conquest of colonies and other states in World War II. In February 1942 in Japan, laws were passed establishing the Wartime Finance Bank and the Southern Development Bank. Both institutions issued bonds to raise funds. The former loaned money primarily to military industries, but also to a wide range of other ventures, including hydroelectric generators, electric power companies, shipbuilding and petroleum. The latter provided financial services in areas occupied by the Japanese military, and Southern Development Bank notes were in fact used as de facto military scrip. In December 1942, the outstanding balance of Southern Development Bank notes stood at more than 470ย million; in March 1945, more than 13ย billion.

Already engaged in war with China, in 1940 the Japanese expanded the scope of their military operations in Asia and finally entered the Second World War in late 1941 with the attack on Pearl Harbor. Japan invaded various Asian countries, occupying vast territories and setting up military administrations.

Beginning with the capture of the Philippines, the Japanese military confiscated all hard currency, both on a federal and individual level, replacing it with locally printed notes bearing a proclamation of military issue. All notes bore the name of the Imperial Japanese government, and some notes proclaimed the "promises to pay the bearer on demand". Called โ€œMickey Mouse Money" by local Filipinos, it was valueless after the overthrow of the Japanese, and tons of it were burned. Japanese troops were ordered to destroy bank records and any remaining currency prior to capitulation.

With the end of World War II, the currency circulated bearing the Japanese name immediately lost any value it once possessed and was discarded en masse. Money that was issued included the Philippines, Burma (now Myanmar), Malaya, North Borneo and Sarawak (now Malaysia), Singapore, Brunei, the Dutch East Indies (now Indonesia) and some areas of Oceania (New Guinea and the Solomon and Gilbert islands). Large amounts of the currency were obtained by Allied forces and civilians at the end of the war; many were kept as wartime souvenirs, and are now in both private and museum collections.

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๐Ÿ”— Holodomor

๐Ÿ”— Human rights ๐Ÿ”— Soviet Union ๐Ÿ”— Crime ๐Ÿ”— Death ๐Ÿ”— Philosophy ๐Ÿ”— Discrimination ๐Ÿ”— Philosophy/Ethics ๐Ÿ”— Soviet Union/history of Russia ๐Ÿ”— Soviet Union/Russia ๐Ÿ”— Ukraine ๐Ÿ”— Ethnic groups

The Holodomor (Ukrainian: ะ“ะพะปะพะดะพะผะพฬั€; ะ“ะพะปะพะดะพะผะพฬั€ ะฒ ะฃะบั€ะฐั—ฬะฝั–; derived from ะผะพั€ะธั‚ะธ ะณะพะปะพะดะพะผ, "to kill by starvation") was a man-made famine in Soviet Ukraine in 1932 and 1933 that killed millions of Ukrainians. It is also known as the Terror-Famine and Famine-Genocide in Ukraine, and sometimes referred to as the Great Famine or the Ukrainian Genocide of 1932โ€“33. It was part of the wider Soviet famine of 1932โ€“33, which affected the major grain-producing areas of the country. During the Holodomor, millions of inhabitants of Ukraine, the majority of whom were ethnic Ukrainians, died of starvation in a peacetime catastrophe unprecedented in the history of Ukraine. Since 2006, the Holodomor has been recognized by Ukraine and 15 other countries as a genocide of the Ukrainian people carried out by the Soviet government.

Early estimates of the death toll by scholars and government officials varied greatly. According to higher estimates, up to 12 million ethnic Ukrainians were said to have perished as a result of the famine. A U.N. joint statement signed by 25 countries in 2003 declared that 7โ€“10 million perished. Research has since narrowed the estimates to between 3.3 and 7.5 million. According to the findings of the Court of Appeal of Kiev in 2010, the demographic losses due to the famine amounted to 10 million, with 3.9 million direct famine deaths, and a further 6.1 million birth deficits.

The term Holodomor emphasises the famine's man-made and intentional aspects, such as rejection of outside aid, confiscation of all household foodstuffs, and restriction of population movement. Whether the Holodomor was genocide is still the subject of academic debate, as are the causes of the famine and intentionality of the deaths. Some scholars believe that the famine was planned by Joseph Stalin to eliminate a Ukrainian independence movement. The loss of life has been compared to that of the Holocaust. However, some historians dispute its characterization as a genocide.

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๐Ÿ”— We (Novel)

๐Ÿ”— Novels ๐Ÿ”— Novels/Science fiction

We (Russian: ะœั‹, romanized:ย My) is a dystopian novel by Russian writer Yevgeny Zamyatin, written 1920โ€“1921. The novel was first published as an English translation by Gregory Zilboorg in 1924 by E. P. Dutton in New York. The novel describes a world of harmony and conformity within a united totalitarian state. George Orwell claimed that Aldous Huxley's 1931 Brave New World must be partly derived from We, but Huxley denied it.

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๐Ÿ”— Sequoyah โ€“ Inventor of the Cherokee Script

๐Ÿ”— Biography ๐Ÿ”— Writing systems ๐Ÿ”— Indigenous peoples of North America ๐Ÿ”— Oklahoma

Sequoyah (แแแ‰แฏ Ssiquoya, as he signed his name, or แŽแ‰แฏ Se-quo-ya, as is often spelled in Cherokee; named in English George Gist or George Guess) (c.1770โ€“1843), was a Native American polymath of the Cherokee Nation. In 1821 he completed his independent creation of a Cherokee syllabary, making reading and writing in Cherokee possible. This was one of the very few times in recorded history that a member of a pre-literate people created an original, effective writing system (another example being Shong Lue Yang). After seeing its worth, the people of the Cherokee Nation rapidly began to use his syllabary and officially adopted it in 1825. Their literacy rate quickly surpassed that of surrounding European-American settlers.

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๐Ÿ”— Red Sea Dam

๐Ÿ”— Africa ๐Ÿ”— Energy ๐Ÿ”— Africa/Djibouti ๐Ÿ”— Yemen

The Red Sea dam is a speculative macro-engineering proposal put forward in 2007 by a group of scientists and engineers. Although the authors' intentions are to explore "the ethical and environmental dilemmas and some of the political implications of macro-engineering", the proposal has attracted both criticism and ridicule.

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๐Ÿ”— Bitmessage: a decentralized, encrypted, trustless communications protocol

๐Ÿ”— Internet ๐Ÿ”— Computing ๐Ÿ”— Telecommunications ๐Ÿ”— Cryptography ๐Ÿ”— Cryptography/Computer science

Bitmessage is a decentralized, encrypted, peer-to-peer, trustless communications protocol that can be used by one person to send encrypted messages to another person, or to multiple subscribers.

In June 2013, the software experienced a surge of new adoptions after news reports of email surveillance by the US National Security Agency.

Bitmessage was conceived by software developer Jonathan Warren, who based its design on the decentralized digital currency, bitcoin. The software was released in November 2012 under the MIT license.

Bitmessage gained a reputation for being out of reach of warrantless wiretapping conducted by the National Security Agency (NSA), due to the decentralized nature of the protocol, and its encryption being difficult to crack. As a result, downloads of the Bitmessage program increased fivefold during June 2013, after news broke of classified email surveillance activities conducted by the NSA.

Bitmessage has also been mentioned as an experimental alternative to email by Popular Science and CNET.

Some ransomware programs instruct affected users to use Bitmessage to communicate with the attackers.